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<div><main class="page"><div class="theme-vdoing-wrapper "><div class="articleInfo-wrap" data-v-06225672><div class="articleInfo" data-v-06225672><ul class="breadcrumbs" data-v-06225672><li data-v-06225672><a href="/" title="首页" class="iconfont icon-home router-link-active" data-v-06225672></a></li> <li data-v-06225672><a href="/back/#后端" data-v-06225672>后端</a></li><li data-v-06225672><a href="/back/#Java笔记" data-v-06225672>Java笔记</a></li></ul> <div class="info" data-v-06225672><div title="作者" class="author iconfont icon-touxiang" data-v-06225672><a href="https://github.com/linxin1123" target="_blank" title="作者" class="beLink" data-v-06225672>lingxin</a></div> <div title="创建时间" class="date iconfont icon-riqi" data-v-06225672><a href="javascript:;" data-v-06225672>2023-01-25</a></div> <!----></div></div></div> <!----> <div class="content-wrapper"><div class="right-menu-wrapper"><div class="right-menu-margin"><div class="right-menu-title">目录</div> <div class="right-menu-content"></div></div></div> <h1><img src="">Java io流（二）<!----></h1>  <div class="theme-vdoing-content content__default"><h1 id="java-io-缓冲流"><a href="#java-io-缓冲流" class="header-anchor">#</a> Java io 缓冲流</h1> <h2 id="_1-字节缓冲流-bos-bis"><a href="#_1-字节缓冲流-bos-bis" class="header-anchor">#</a> 1. 字节缓冲流(bos,bis)</h2> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>BufferedOutputStream(OutputStream out)</td> <td>创建字节缓冲输出流对象</td></tr> <tr><td>BufferedInputStream(InputStream in)</td> <td>创建字节缓冲输入流</td></tr></tbody></table> <h3 id="_1-2-字节缓冲流复制视频"><a href="#_1-2-字节缓冲流复制视频" class="header-anchor">#</a> 1.2 字节缓冲流复制视频</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo2</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>


<span class="token comment">//        3.基本字节流-输出流</span>

        <span class="token class-name">FileOutputStream</span> fos <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileOutputStream</span><span class="token punctuation">(</span><span class="token string">&quot;code\\1.mp4&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">FileInputStream</span> fis <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileInputStream</span><span class="token punctuation">(</span><span class="token string">&quot;E:\\javascript代码\\jsBOM和DOM\\day06&quot;</span> <span class="token operator">+</span>
                <span class="token string">&quot;\\07.zy.media.js插件的使用\\mov.mp4&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token comment">//        1.复制视频，比较各个复制的效率，缓冲输出流</span>
        <span class="token class-name">BufferedOutputStream</span> bos <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedOutputStream</span><span class="token punctuation">(</span>fos<span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        2.缓冲输入流</span>

        <span class="token class-name">BufferedInputStream</span> bis <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedInputStream</span><span class="token punctuation">(</span>fis<span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        开始时间</span>

        <span class="token keyword">long</span> startTime<span class="token operator">=</span> <span class="token class-name">System</span><span class="token punctuation">.</span><span class="token function">currentTimeMillis</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        method1(bos,bis);   26ms  缓冲区单个字节</span>
<span class="token comment">//        method2(bos,bis);   2ms   缓冲区 字节数组</span>
<span class="token comment">//        method3(fis,fos);   3021ms   基本字节流-单个字节</span>
<span class="token comment">//        method4(fis,fos);   3157      基本字节流-字节数组</span>



        <span class="token keyword">long</span> endTime<span class="token operator">=</span><span class="token class-name">System</span><span class="token punctuation">.</span><span class="token function">currentTimeMillis</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span><span class="token string">&quot;总时间&quot;</span><span class="token operator">+</span><span class="token punctuation">(</span>endTime<span class="token operator">-</span>startTime<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

    <span class="token punctuation">}</span>
    <span class="token comment">//        一个一个字节的复制</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">method1</span><span class="token punctuation">(</span><span class="token class-name">BufferedOutputStream</span> bos<span class="token punctuation">,</span><span class="token class-name">BufferedInputStream</span> bis<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
        <span class="token keyword">int</span> bt<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>bt<span class="token operator">=</span>bis<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            bos<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>bt<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>

<span class="token comment">//    2.使用字节数组获取原来</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">method2</span><span class="token punctuation">(</span><span class="token class-name">BufferedOutputStream</span> bos<span class="token punctuation">,</span><span class="token class-name">BufferedInputStream</span> bis<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
        <span class="token keyword">byte</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>bts<span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">byte</span><span class="token punctuation">[</span><span class="token number">1024</span><span class="token punctuation">]</span><span class="token punctuation">;</span>
        <span class="token keyword">int</span> len<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>bis<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span>bts<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            bos<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>bts<span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">,</span>len<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>

<span class="token comment">//    1.基本字节流一个一个写</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">method3</span><span class="token punctuation">(</span><span class="token class-name">FileInputStream</span> fis<span class="token punctuation">,</span><span class="token class-name">FileOutputStream</span> fos<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
        <span class="token keyword">int</span> bt<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>bt<span class="token operator">=</span>fis<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            fos<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>bt<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>

<span class="token comment">//    2.基本字节流字节数组</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">method4</span><span class="token punctuation">(</span><span class="token class-name">FileInputStream</span> fis<span class="token punctuation">,</span><span class="token class-name">FileOutputStream</span> fos<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>

        <span class="token keyword">byte</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>bts<span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">byte</span><span class="token punctuation">[</span><span class="token number">1024</span><span class="token punctuation">]</span><span class="token punctuation">;</span>
        <span class="token keyword">int</span> len<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>fis<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            fos<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>bts<span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">,</span>len<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>


<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br><span class="line-number">41</span><br><span class="line-number">42</span><br><span class="line-number">43</span><br><span class="line-number">44</span><br><span class="line-number">45</span><br><span class="line-number">46</span><br><span class="line-number">47</span><br><span class="line-number">48</span><br><span class="line-number">49</span><br><span class="line-number">50</span><br><span class="line-number">51</span><br><span class="line-number">52</span><br><span class="line-number">53</span><br><span class="line-number">54</span><br><span class="line-number">55</span><br><span class="line-number">56</span><br><span class="line-number">57</span><br><span class="line-number">58</span><br><span class="line-number">59</span><br><span class="line-number">60</span><br><span class="line-number">61</span><br><span class="line-number">62</span><br><span class="line-number">63</span><br><span class="line-number">64</span><br><span class="line-number">65</span><br><span class="line-number">66</span><br><span class="line-number">67</span><br><span class="line-number">68</span><br><span class="line-number">69</span><br><span class="line-number">70</span><br><span class="line-number">71</span><br><span class="line-number">72</span><br><span class="line-number">73</span><br><span class="line-number">74</span><br><span class="line-number">75</span><br></div></div><h4 id="结论"><a href="#结论" class="header-anchor">#</a> 结论</h4> <ul><li><strong>缓冲流字节数组效率最高，基本字节流字节数组最慢</strong></li></ul> <h2 id="_2-字符流"><a href="#_2-字符流" class="header-anchor">#</a> 2. 字符流</h2> <ul><li><strong>定义：字符流=字节流+编码表，便于操作中文</strong></li></ul> <h3 id="_2-1-常见的编码表"><a href="#_2-1-常见的编码表" class="header-anchor">#</a> 2.1 常见的编码表</h3> <ul><li><p>常见字符集</p> <ul><li><strong>ascll字符集</strong></li> <li><strong>GBK字符集</strong>：常用的中文编码，20000+汉字</li> <li><strong>unicode字符集</strong>：UTF-8编码：万国码，一至4个字节</li></ul></li> <li><p>编码形式：</p> <ul><li>ascll：一个字节编码</li> <li>拉丁文等字符，两个字节编码</li> <li>大部分常用字（包含中文），3个字节编码</li> <li>极少使用的Unicode辅助字符，4字节编码</li></ul></li></ul> <h3 id="_2-2-字符串的编码解码问题"><a href="#_2-2-字符串的编码解码问题" class="header-anchor">#</a> 2.2 字符串的编码解码问题</h3> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>bytes[]  getBytes()</td> <td>使用平台默认字符集编码字节</td></tr> <tr><td>bytes[]  getBytes(String charsetName)</td> <td>使用参数里的字符集编码字节</td></tr> <tr><td>String(bytes[])</td> <td>使用默认字符集解码成字符串</td></tr> <tr><td>String(bytes[],String charsetName)</td> <td>使用参数里的字符集解码成字符串</td></tr></tbody></table> <h4 id="示例"><a href="#示例" class="header-anchor">#</a> 示例</h4> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">UnsupportedEncodingException</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo3</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">UnsupportedEncodingException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.定义一个字符串</span>

        <span class="token class-name">String</span> str<span class="token operator">=</span><span class="token string">&quot;中国&quot;</span><span class="token punctuation">;</span>

<span class="token comment">//        2.使用默认字符集编码</span>

        <span class="token keyword">byte</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>arr<span class="token operator">=</span>str<span class="token punctuation">.</span><span class="token function">getBytes</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">byte</span> i<span class="token operator">:</span>arr<span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">print</span><span class="token punctuation">(</span>i<span class="token punctuation">)</span><span class="token punctuation">;</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">print</span><span class="token punctuation">(</span><span class="token string">&quot;,&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

<span class="token comment">//        3.使用GBK编码</span>

        <span class="token keyword">byte</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>arr1<span class="token operator">=</span>str<span class="token punctuation">.</span><span class="token function">getBytes</span><span class="token punctuation">(</span><span class="token string">&quot;GBK&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">byte</span> i<span class="token operator">:</span>arr<span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">print</span><span class="token punctuation">(</span>i<span class="token operator">+</span><span class="token string">&quot;,&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>


<span class="token comment">//        使用默认的字符集解码</span>

        <span class="token class-name">String</span> str1<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">String</span><span class="token punctuation">(</span>arr<span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>str1<span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        使用GBK解码</span>
        <span class="token class-name">String</span> str2<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">String</span><span class="token punctuation">(</span>arr1<span class="token punctuation">,</span><span class="token string">&quot;GBK&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>str2<span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/94af6fa7de764c2c8e625603ab165fa8.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-3-字符流中的编码解码问题"><a href="#_2-3-字符流中的编码解码问题" class="header-anchor">#</a> 2.3 字符流中的编码解码问题</h3> <ul><li><strong>InputStreamReader：是从字节流到字符流的桥梁</strong></li> <li><strong>OutputStreamWriter：是从字符流到字节流的桥梁</strong></li></ul> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>InputStreamReader(InputStream in)</td> <td>使用默认编码创建InputStreamReader对象</td></tr> <tr><td>InputStreamReader（InputStream  in，String chasetName）</td> <td>使用参数的编码创建InputStreamReader对象</td></tr> <tr><td>OutputStreamWriter（OutputStream  out）</td> <td>使用默认编码创建osw对象</td></tr> <tr><td>OutputStreamWriter（OutputStream out，String chasetName）</td> <td>使用参数的编码创建osw</td></tr></tbody></table> <h4 id="示例-2"><a href="#示例-2" class="header-anchor">#</a> 示例</h4> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo4</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>

<span class="token comment">//        1.使用默认的编码创建InputStreamReader对象</span>
        <span class="token class-name">FileInputStream</span> fis <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileInputStream</span><span class="token punctuation">(</span><span class="token string">&quot;code\\2.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">FileOutputStream</span> fos <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileOutputStream</span><span class="token punctuation">(</span><span class="token string">&quot;code\\3.txt&quot;</span><span class="token punctuation">,</span><span class="token boolean">true</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token class-name">InputStreamReader</span> isr <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">InputStreamReader</span><span class="token punctuation">(</span>fis<span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        2.使用默认的编码创建OutStreamWriter对象</span>

        <span class="token class-name">OutputStreamWriter</span> osw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">OutputStreamWriter</span><span class="token punctuation">(</span>fos<span class="token punctuation">,</span><span class="token string">&quot;GBK&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        直接使用字符写入数据，默认编码</span>

        osw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span><span class="token string">&quot;中国&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        int bt=isr.read();</span>
<span class="token comment">//        char cbt=(char)bt;</span>
<span class="token comment">//        System.out.println(cbt);</span>

<span class="token comment">//        2.读取数组</span>
        <span class="token keyword">int</span> bt<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>bt<span class="token operator">=</span>isr<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">print</span><span class="token punctuation">(</span><span class="token punctuation">(</span><span class="token keyword">char</span><span class="token punctuation">)</span>bt<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        osw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        isr<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>


    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/4a67a00e3dff443180518ce81801dda1.gif#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-4-字符流写数据的方法"><a href="#_2-4-字符流写数据的方法" class="header-anchor">#</a> 2.4 字符流写数据的方法</h3> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>void write(int c)</td> <td>写入一个字符</td></tr> <tr><td>void write(byte []bys)</td> <td>写入一个字符数组</td></tr> <tr><td>void write(byte []bys int off,int len)</td> <td>写入字符数组的一部分</td></tr> <tr><td>void write(String str)</td> <td>写入一个字符串</td></tr> <tr><td>void write(String str,int off,int len)</td> <td>写入字符串的一部分</td></tr></tbody></table> <ul><li>刷新和关闭的方法</li></ul> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>flush()</td> <td>刷新流，之后可以继续写数据</td></tr> <tr><td>close()</td> <td>关闭流，释放资源，关闭之前会刷新流</td></tr></tbody></table> <h4 id="示例-3"><a href="#示例-3" class="header-anchor">#</a> 示例</h4> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileNotFoundException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileOutputStream</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">IOException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">OutputStreamWriter</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo5</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.创建输出流-字符输出流</span>

        <span class="token class-name">FileOutputStream</span> fos <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileOutputStream</span><span class="token punctuation">(</span><span class="token string">&quot;code\\2.txt&quot;</span><span class="token punctuation">,</span><span class="token boolean">true</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token class-name">OutputStreamWriter</span> osw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">OutputStreamWriter</span><span class="token punctuation">(</span>fos<span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        写入一个字符</span>

        osw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span><span class="token char">'a'</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        写入一个字符数组</span>
        <span class="token keyword">char</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>bys<span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">char</span><span class="token punctuation">[</span><span class="token punctuation">]</span><span class="token punctuation">{</span><span class="token char">'a'</span><span class="token punctuation">,</span><span class="token char">'b'</span><span class="token punctuation">,</span><span class="token char">'c'</span><span class="token punctuation">,</span><span class="token char">'d'</span><span class="token punctuation">,</span><span class="token char">'e'</span><span class="token punctuation">}</span><span class="token punctuation">;</span>

        osw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>bys<span class="token punctuation">,</span><span class="token number">1</span><span class="token punctuation">,</span><span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token comment">//       写入一个字符串</span>

        osw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span><span class="token string">&quot;abcdefgh&quot;</span><span class="token punctuation">,</span><span class="token number">2</span><span class="token punctuation">,</span><span class="token number">5</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        osw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/d3dbb61adaed48bb9e4518a5d4c0b9ba.png#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-5-字符流读数据的方法"><a href="#_2-5-字符流读数据的方法" class="header-anchor">#</a> 2.5 字符流读数据的方法</h3> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>int read()</td> <td>一次读一个字符</td></tr> <tr><td>int read(char[] cbuf)</td> <td>一次读一个字符数组</td></tr></tbody></table> <h4 id="示例-4"><a href="#示例-4" class="header-anchor">#</a> 示例</h4> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileInputStream</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileNotFoundException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">IOException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">InputStreamReader</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo6</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.创建字符输入流对象</span>

        <span class="token class-name">FileInputStream</span> fis <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileInputStream</span><span class="token punctuation">(</span><span class="token string">&quot;code\\3.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">InputStreamReader</span> isr <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">InputStreamReader</span><span class="token punctuation">(</span>fis<span class="token punctuation">,</span><span class="token string">&quot;GBK&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        一次读一个字符</span>
        <span class="token keyword">int</span> ch<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>ch<span class="token operator">=</span>isr<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">print</span><span class="token punctuation">(</span><span class="token punctuation">(</span><span class="token keyword">char</span><span class="token punctuation">)</span>ch<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

<span class="token comment">//        一次读一个字符数组</span>



        <span class="token keyword">char</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>chs<span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">char</span><span class="token punctuation">[</span><span class="token number">1024</span><span class="token punctuation">]</span><span class="token punctuation">;</span>
        <span class="token keyword">int</span> len<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>isr<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span>chs<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">print</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">String</span><span class="token punctuation">(</span>chs<span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">,</span>len<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        isr<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/d2b46bdb096545bd8e1b577b8dfa0d32.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-6-字符流复制文件-isr-osw"><a href="#_2-6-字符流复制文件-isr-osw" class="header-anchor">#</a> 2.6 字符流复制文件(isr,osw)</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo7</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.创建字符流输入输出对象</span>
        <span class="token class-name">FileInputStream</span> fis <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileInputStream</span><span class="token punctuation">(</span><span class="token string">&quot;F:\\BaiduNetdiskDownload\\第八卷生肉.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token keyword">final</span> <span class="token class-name">FileOutputStream</span> fos <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileOutputStream</span><span class="token punctuation">(</span><span class="token string">&quot;code\\4.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">InputStreamReader</span> isr <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">InputStreamReader</span><span class="token punctuation">(</span>fis<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">OutputStreamWriter</span> osw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">OutputStreamWriter</span><span class="token punctuation">(</span>fos<span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token keyword">int</span> len<span class="token punctuation">;</span>
        <span class="token keyword">char</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>chs<span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">char</span><span class="token punctuation">[</span><span class="token number">1024</span><span class="token punctuation">]</span><span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>isr<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span>chs<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            osw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>chs<span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">,</span>len<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/c29c7727e5db4683abcb8c84d1b4d972.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-7-便捷流复制文件-filereader"><a href="#_2-7-便捷流复制文件-filereader" class="header-anchor">#</a> 2.7 便捷流复制文件(FileReader)</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo8</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.使用便捷流复制文件</span>


<span class="token comment">//        1.创建便捷流对象</span>
        <span class="token class-name">FileReader</span> fr <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileReader</span><span class="token punctuation">(</span><span class="token string">&quot;F:\\BaiduNetdiskDownload\\第八卷生肉.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">FileWriter</span> fw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">FileWriter</span><span class="token punctuation">(</span><span class="token string">&quot;code\\5.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token keyword">int</span> len<span class="token punctuation">;</span>
        <span class="token keyword">char</span> chs<span class="token punctuation">[</span><span class="token punctuation">]</span><span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">char</span><span class="token punctuation">[</span><span class="token number">1024</span><span class="token punctuation">]</span><span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>fr<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span>chs<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            fw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>chs<span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">,</span>len<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/3712f198d2094b6594a0ff5b866ffd9f.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-8-字符缓冲流"><a href="#_2-8-字符缓冲流" class="header-anchor">#</a> 2.8 字符缓冲流</h3> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>BufferedWriter(Write out)</td> <td>创建字符缓冲输出流对象</td></tr> <tr><td>BufferedReader(Reader in)</td> <td>创建字符缓冲输入流对象</td></tr></tbody></table> <h4 id="示例-5"><a href="#示例-5" class="header-anchor">#</a> 示例</h4> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo9</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.字符流缓冲复制文件</span>

        <span class="token class-name">BufferedReader</span> br <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedReader</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileReader</span><span class="token punctuation">(</span><span class="token string">&quot;F:\\BaiduNetdiskDownload\\第八卷生肉.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">BufferedWriter</span> bw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedWriter</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileWriter</span><span class="token punctuation">(</span><span class="token string">&quot;code\\6.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>


<span class="token comment">//        以字符数组的形式复制</span>

        <span class="token keyword">int</span> len<span class="token punctuation">;</span>
        <span class="token keyword">char</span> <span class="token punctuation">[</span><span class="token punctuation">]</span>chs<span class="token operator">=</span><span class="token keyword">new</span> <span class="token keyword">char</span><span class="token punctuation">[</span><span class="token number">1024</span><span class="token punctuation">]</span><span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>br<span class="token punctuation">.</span><span class="token function">read</span><span class="token punctuation">(</span>chs<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            bw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>chs<span class="token punctuation">,</span><span class="token number">0</span><span class="token punctuation">,</span>len<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        br<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        bw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/81672860209743138312f8333fa3f675.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_2-9-字符缓冲流的特有方法"><a href="#_2-9-字符缓冲流的特有方法" class="header-anchor">#</a> 2.9 字符缓冲流的特有方法</h3> <ul><li><strong>BufferedWriter</strong></li></ul> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>void newLine()</td> <td>写一行分隔符，行风格字符串由系统属性定义</td></tr></tbody></table> <ul><li><strong>BufferedReader</strong></li></ul> <table><thead><tr><th>方法名</th> <th>说明</th></tr></thead> <tbody><tr><td>String readLine()</td> <td>读一行文字，结果包含行的内容字符串，不包括任何终止字符，如果流的结尾已经到达，则为null</td></tr></tbody></table> <h4 id="示例-6"><a href="#示例-6" class="header-anchor">#</a> 示例</h4> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo10</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.创建字符缓冲流</span>

        <span class="token class-name">BufferedReader</span> br <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedReader</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileReader</span><span class="token punctuation">(</span><span class="token string">&quot;code\\5.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">BufferedWriter</span> bw<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">BufferedWriter</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileWriter</span><span class="token punctuation">(</span><span class="token string">&quot;code\\5.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//      1.往5.txt写数据</span>

        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token keyword">int</span> i<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span>i<span class="token operator">&lt;</span><span class="token number">10</span><span class="token punctuation">;</span>i<span class="token operator">++</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            bw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span><span class="token string">&quot;hello&quot;</span><span class="token operator">+</span>i<span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">newLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">flush</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        bw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        2.从5.txt中读取数据</span>

        <span class="token class-name">String</span> len<span class="token punctuation">;</span>
<span class="token comment">//        char []chs=new char[1024];</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>len<span class="token operator">=</span>br<span class="token punctuation">.</span><span class="token function">readLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token keyword">null</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>len<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/9cf3ef9dffc541d09d3ee45ecff1c712.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h2 id="_3-总结"><a href="#_3-总结" class="header-anchor">#</a> 3. 总结</h2> <p><img src="https://img-blog.csdnimg.cn/4c32469677904ec78f1cd035a86634e3.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <p><img src="https://img-blog.csdnimg.cn/b0c9f77f0d3247ed95b624d7595be90e.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <ul><li><strong>更多关于io流的类推荐查看jdk文档</strong></li></ul> <h2 id="_4-案例"><a href="#_4-案例" class="header-anchor">#</a> 4.案例</h2> <h3 id="_4-1-文件内容到集合"><a href="#_4-1-文件内容到集合" class="header-anchor">#</a> 4.1 文件内容到集合</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">BufferedReader</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileNotFoundException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileReader</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">IOException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>util<span class="token punctuation">.</span></span><span class="token class-name">ArrayList</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> demo11 <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.创建字符缓冲对象</span>
        <span class="token class-name">BufferedReader</span> br <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedReader</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileReader</span><span class="token punctuation">(</span><span class="token string">&quot;code\\5.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">String</span><span class="token punctuation">&gt;</span></span> strs <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">String</span><span class="token punctuation">&gt;</span></span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">String</span> s<span class="token punctuation">;</span>
<span class="token comment">//        1.每一行添加到集合</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>s<span class="token operator">=</span>br<span class="token punctuation">.</span><span class="token function">readLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token keyword">null</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            strs<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        br<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token comment">//      1.遍历集合</span>
        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token class-name">String</span> line <span class="token operator">:</span> strs<span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>line<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/64d4868327e744e897b007e878d62331.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_4-2-集合到文件"><a href="#_4-2-集合到文件" class="header-anchor">#</a> 4.2 集合到文件</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">BufferedWriter</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileWriter</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">IOException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>util<span class="token punctuation">.</span></span><span class="token class-name">ArrayList</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">Demo12</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
<span class="token comment">//        1.创建字符缓冲流对象</span>
        <span class="token class-name">BufferedWriter</span> bw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedWriter</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileWriter</span><span class="token punctuation">(</span><span class="token string">&quot;code\\6.txt&quot;</span><span class="token punctuation">,</span><span class="token boolean">true</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">String</span><span class="token punctuation">&gt;</span></span> strs <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">String</span><span class="token punctuation">&gt;</span></span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        strs<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span><span class="token string">&quot;hello&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        strs<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span><span class="token string">&quot;world&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        strs<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span><span class="token string">&quot;happy&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        遍历集合，写数据到文件</span>

        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token class-name">String</span> s<span class="token operator">:</span>strs<span class="token punctuation">)</span><span class="token punctuation">{</span>
            bw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>s<span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">newLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">flush</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        bw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/10b194d852a34f2eb75cb7f9ef0343b4.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_4-3-学生对象到文件"><a href="#_4-3-学生对象到文件" class="header-anchor">#</a> 4.3 学生对象到文件</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">BufferedWriter</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">FileWriter</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token class-name">IOException</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>util<span class="token punctuation">.</span></span><span class="token class-name">ArrayList</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">StudentsTest</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
        <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">Student</span><span class="token punctuation">&gt;</span></span> students <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">Student</span><span class="token punctuation">&gt;</span></span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s1<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">12</span><span class="token punctuation">,</span><span class="token string">&quot;bob&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima001&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;北京&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s2<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">13</span><span class="token punctuation">,</span><span class="token string">&quot;kate&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima002&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;西安&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s3<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">14</span><span class="token punctuation">,</span><span class="token string">&quot;peter&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima003&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;娄底&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s4<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">15</span><span class="token punctuation">,</span><span class="token string">&quot;judy&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima004&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;湖南&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token class-name">BufferedWriter</span> bw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedWriter</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileWriter</span><span class="token punctuation">(</span><span class="token string">&quot;code\\7.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s1<span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s2<span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s3<span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s4<span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token class-name">Student</span> s<span class="token operator">:</span>students<span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">String</span> str<span class="token operator">=</span><span class="token string">&quot;年龄：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getAge</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 姓名：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getName</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 学号：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getSid</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 地址：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getAddress</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>str<span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">newLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">flush</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        bw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/60da53f3b4f243b9a52e7c0faebbf556.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p> <h3 id="_4-4-文件到学生对象"><a href="#_4-4-文件到学生对象" class="header-anchor">#</a> 4.4 文件到学生对象</h3> <div class="language-java line-numbers-mode"><pre class="language-java"><code><span class="token keyword">package</span> <span class="token namespace">second</span><span class="token punctuation">;</span>

<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>io<span class="token punctuation">.</span></span><span class="token operator">*</span></span><span class="token punctuation">;</span>
<span class="token keyword">import</span> <span class="token import"><span class="token namespace">java<span class="token punctuation">.</span>util<span class="token punctuation">.</span></span><span class="token class-name">ArrayList</span></span><span class="token punctuation">;</span>

<span class="token keyword">public</span> <span class="token keyword">class</span> <span class="token class-name">StudentsTest</span> <span class="token punctuation">{</span>
    <span class="token keyword">public</span> <span class="token keyword">static</span> <span class="token keyword">void</span> <span class="token function">main</span><span class="token punctuation">(</span><span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> args<span class="token punctuation">)</span> <span class="token keyword">throws</span> <span class="token class-name">IOException</span> <span class="token punctuation">{</span>
        <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">Student</span><span class="token punctuation">&gt;</span></span> students <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">ArrayList</span><span class="token generics"><span class="token punctuation">&lt;</span><span class="token class-name">Student</span><span class="token punctuation">&gt;</span></span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s1<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">12</span><span class="token punctuation">,</span><span class="token string">&quot;bob&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima001&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;北京&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s2<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">13</span><span class="token punctuation">,</span><span class="token string">&quot;kate&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima002&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;西安&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s3<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">14</span><span class="token punctuation">,</span><span class="token string">&quot;peter&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima003&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;娄底&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">Student</span> s4<span class="token operator">=</span><span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token number">15</span><span class="token punctuation">,</span><span class="token string">&quot;judy&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;heima004&quot;</span><span class="token punctuation">,</span><span class="token string">&quot;湖南&quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token class-name">BufferedWriter</span> bw <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedWriter</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileWriter</span><span class="token punctuation">(</span><span class="token string">&quot;code\\7.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s1<span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s2<span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s3<span class="token punctuation">)</span><span class="token punctuation">;</span>
        students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>s4<span class="token punctuation">)</span><span class="token punctuation">;</span>

        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token class-name">Student</span> s<span class="token operator">:</span>students<span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">String</span> str<span class="token operator">=</span><span class="token string">&quot;年龄：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getAge</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 姓名：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getName</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 学号：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getSid</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 地址：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getAddress</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">write</span><span class="token punctuation">(</span>str<span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">newLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            bw<span class="token punctuation">.</span><span class="token function">flush</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        bw<span class="token punctuation">.</span><span class="token function">close</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">//        文件到对象</span>

        <span class="token class-name">BufferedReader</span> br <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">BufferedReader</span><span class="token punctuation">(</span><span class="token keyword">new</span> <span class="token class-name">FileReader</span><span class="token punctuation">(</span><span class="token string">&quot;code\\7.txt&quot;</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token class-name">String</span> str<span class="token punctuation">;</span>
        <span class="token keyword">while</span><span class="token punctuation">(</span><span class="token punctuation">(</span>str<span class="token operator">=</span>br<span class="token punctuation">.</span><span class="token function">readLine</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token operator">!=</span><span class="token keyword">null</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">String</span><span class="token punctuation">[</span><span class="token punctuation">]</span> strs <span class="token operator">=</span> str<span class="token punctuation">.</span><span class="token function">split</span><span class="token punctuation">(</span><span class="token string">&quot; &quot;</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            <span class="token class-name">Student</span> student <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Student</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            <span class="token keyword">int</span> num<span class="token operator">=</span><span class="token number">0</span><span class="token punctuation">;</span>
            <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token class-name">String</span> s<span class="token operator">:</span>strs<span class="token punctuation">)</span><span class="token punctuation">{</span>
                s<span class="token operator">=</span>s<span class="token punctuation">.</span><span class="token function">substring</span><span class="token punctuation">(</span><span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
                <span class="token keyword">if</span><span class="token punctuation">(</span>num<span class="token operator">==</span><span class="token number">0</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                    student<span class="token punctuation">.</span><span class="token function">setAge</span><span class="token punctuation">(</span><span class="token class-name">Integer</span><span class="token punctuation">.</span><span class="token function">parseInt</span><span class="token punctuation">(</span>s<span class="token punctuation">)</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
                <span class="token punctuation">}</span><span class="token keyword">else</span> <span class="token keyword">if</span><span class="token punctuation">(</span>num<span class="token operator">==</span><span class="token number">1</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                    student<span class="token punctuation">.</span><span class="token function">setName</span><span class="token punctuation">(</span>s<span class="token punctuation">)</span><span class="token punctuation">;</span>
                <span class="token punctuation">}</span><span class="token keyword">else</span> <span class="token keyword">if</span><span class="token punctuation">(</span>num<span class="token operator">==</span><span class="token number">2</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                    student<span class="token punctuation">.</span><span class="token function">setSid</span><span class="token punctuation">(</span>s<span class="token punctuation">)</span><span class="token punctuation">;</span>
                <span class="token punctuation">}</span><span class="token keyword">else</span> <span class="token keyword">if</span><span class="token punctuation">(</span>num<span class="token operator">==</span><span class="token number">3</span><span class="token punctuation">)</span><span class="token punctuation">{</span>
                    student<span class="token punctuation">.</span><span class="token function">setAddress</span><span class="token punctuation">(</span>s<span class="token punctuation">)</span><span class="token punctuation">;</span>
                <span class="token punctuation">}</span>

                num<span class="token operator">++</span><span class="token punctuation">;</span>
            <span class="token punctuation">}</span>

            students<span class="token punctuation">.</span><span class="token function">add</span><span class="token punctuation">(</span>student<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>

        <span class="token keyword">for</span><span class="token punctuation">(</span><span class="token class-name">Student</span> s<span class="token operator">:</span>students<span class="token punctuation">)</span><span class="token punctuation">{</span>
            <span class="token class-name">String</span> str1<span class="token operator">=</span><span class="token string">&quot;年龄：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getAge</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 姓名：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getName</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 学号：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getSid</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token operator">+</span><span class="token string">&quot; 地址：&quot;</span><span class="token operator">+</span>s<span class="token punctuation">.</span><span class="token function">getAddress</span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
            <span class="token class-name">System</span><span class="token punctuation">.</span>out<span class="token punctuation">.</span><span class="token function">println</span><span class="token punctuation">(</span>str1<span class="token punctuation">)</span><span class="token punctuation">;</span>
        <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br><span class="line-number">38</span><br><span class="line-number">39</span><br><span class="line-number">40</span><br><span class="line-number">41</span><br><span class="line-number">42</span><br><span class="line-number">43</span><br><span class="line-number">44</span><br><span class="line-number">45</span><br><span class="line-number">46</span><br><span class="line-number">47</span><br><span class="line-number">48</span><br><span class="line-number">49</span><br><span class="line-number">50</span><br><span class="line-number">51</span><br><span class="line-number">52</span><br><span class="line-number">53</span><br><span class="line-number">54</span><br><span class="line-number">55</span><br><span class="line-number">56</span><br><span class="line-number">57</span><br><span class="line-number">58</span><br><span class="line-number">59</span><br><span class="line-number">60</span><br><span class="line-number">61</span><br></div></div><ul><li>效果图</li></ul> <p><img src="https://img-blog.csdnimg.cn/24e87479c6e244b7bdda9192c8469182.png?x-oss-process=image/watermark,type_d3F5LXplbmhlaQ,shadow_50,text_Q1NETiBA5YeM5q2G,size_20,color_FFFFFF,t_70,g_se,x_16#pic_center" alt="在这里插入图片描述"></p></div></div>  <div class="page-edit"><div class="edit-link"><a href="https://github.com/linxin1123/vuepress-blog/edit/master/docs/02.后端/41.Java笔记/04.Java io流（二）.md" target="_blank" rel="noopener noreferrer">编辑</a> <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></div> <!----> <div class="last-updated"><span class="prefix">上次更新:</span> <span class="time">2023/02/17, 11:29:32</span></div></div> <div class="page-nav-wapper"><div class="page-nav-centre-wrap"><a href="/pages/c57687/" class="page-nav-centre page-nav-centre-prev"><div class="tooltip">Java io流（一）</div></a> <a href="/pages/2d0d17/" class="page-nav-centre page-nav-centre-next"><div class="tooltip">Java io流（三）</div></a></div> <div class="page-nav"><p class="inner"><span class="prev">
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